A new international study published in the journal Communications Earth & Environment has found that beavers can help reduce carbon dioxide in the air by changing the way rivers and wetlands work. The research was led by scientists from the University of Birmingham, along with other European partners. It focused on an area in northern Switzerland where beavers have been active for more than ten years.
Beavers are slowly returning to many parts of Europe after years of conservation work. As they come back, they are not just rebuilding their populations; they are also reshaping natural environments. This study shows that their impact goes far beyond what was previously understood.
Beavers build dams across streams. These dams slow down water and create small wetlands. As water spreads out, it floods nearby land. This changes how water moves underground and across the surface. It also causes sediments, plants, and other materials to collect in one place.
All of this plays an important role in how carbon is stored. Carbon exists in many forms in nature. It can be found in water, soil, plants, and the air. When beavers create wetlands, they help trap carbon in these systems instead of letting it escape into the atmosphere.
The researchers measured how much carbon was stored in a beaver-managed area. They found that these wetlands can store much more carbon than similar areas without beavers. In fact, the rate was up to ten times higher.
Over a period of 13 years, the study area stored about 1,194 tonnes of carbon. This equals around 10.1 tonnes per hectare each year. This shows that beaver activity can have a strong and lasting effect on carbon storage.
The scientists used many methods to collect their data. They studied water flow, tested chemicals, took soil samples, and monitored greenhouse gases. They also used long-term models to understand how the system changes over time. This made their findings very detailed and reliable.
The results showed that the wetland acted as a net carbon sink. This means it absorbed more carbon than it released. Each year, it stored about 98 tonnes of carbon on average.
However, the process is not the same all year round. In the summer, water levels drop. This exposes more soil and sediment to the air. During this time, some carbon dioxide is released into the atmosphere. For short periods, the system becomes a carbon source instead of a sink. However, over a full year, it still stores more carbon than it releases.
Over time, dead plants, wood, and sediment build up. These materials store carbon for many years, sometimes even decades.
Another important finding was about methane. Wetlands are often known to release methane, which is a powerful greenhouse gas. But in this study, methane emissions were very low. They were less than 0.1% of the total carbon balance. This shows that the wetlands are still very effective at reducing overall emissions.
The study also found that the soil in these wetlands contains a lot of carbon. Sediments had much higher levels of both inorganic and organic carbon compared to nearby forest soils. Dead wood from trees growing near the water also played a big role. It made up nearly half of the long-term stored carbon.
These findings suggest that beaver wetlands are stable and long-lasting carbon storage systems. As long as the dams remain in place, they can continue to store carbon for many years.
The researchers also looked at what could happen on a larger scale. In Switzerland, there are many areas suitable for beavers. If beavers return to all these places, their wetlands could offset between 1.2% and 1.8% of the country’s yearly carbon emissions.
This is important because it shows a natural way to fight climate change. It does not need expensive technology. It works by restoring ecosystems and letting animals do their natural roles. The study shows why rewilding is important. Bringing back beavers can improve the environment in simple ways. These changes help both nature and the climate, but more research is necessary. Scientists want to understand how beavers affect different areas. This will help guide land use and policies. Beavers are more than dam builders; they are ecosystem engineers. They store carbon and improve habitats.
